JP7382270B2 - Wall member for forming a wall body and method for constructing a wall body using the same - Google Patents

Description

The present invention relates to a wall member made of precast concrete for forming a wall body such as a waist wall where a beam is not connected to the upper end, and a method of constructing a wall body using the same. .

Precast concrete wall members, which are used to reduce the number of on-site wall construction tasks, have protruding reinforcement bars (anchor bars) for connecting them to supporting slabs and beams. There are two types: one in which the entire wall is made of precast concrete (see Patent Document 1), and the other in which a part of the wall member is cut out and cast-in-place concrete is placed in the cutout (see Patent Document 2). Separated.

The former form (Patent Document 1) has the advantage of simplifying the work by reducing the number of on-site work since there is no concrete pouring work for the wall member portion. In the latter form (Patent Document 2), when the wall member is formed in a shape in which one side in the thickness direction of the lower side of the wall member is cut out for fixing the insertion line, the cutout side of the wall member This makes it possible to fix the reinforcing bars.

JP-A-6-341179 (Paragraphs 0011 to 0017, Figures 1 and 2) JP-A-9-287196 (Paragraphs 0009 to 0028, Figures 1 to 10)

However, in the former case, since the mass of one wall member becomes large, the handling efficiency during installation is reduced, resulting in a disadvantage that the work efficiency of installation is reduced. In addition, if the slab supporting the wall member is constructed in advance, it may be difficult to fix the reinforcing bars arranged in the slab to the wall member in order to integrate the wall member into the slab. There is.

In the latter case, in areas where the wall thickness is reduced, for example, in areas where cast-in-place concrete is placed, mainly vertical reinforcements inside the wall member intersect with insertion reinforcements protruding from the top surface of the slab. Since there is precast concrete that is part of the wall member in the reinforcement area of these reinforcing bars, the ability to fill the cast-in-place concrete around the vertical bars and insert bars will decrease, and it may not be possible to achieve a dense filling state. There is sex.

In light of the above background, the present invention provides a wall member for forming a wall body that is easy to place reinforcing bars and fill with cast-in-place concrete when a part of the wall body is made of precast concrete. This paper proposes a method for constructing walls using.

The wall member for forming a wall according to claim 1 is arranged on a slab at a distance from the top surface of the slab, and concrete is poured between the top surface of the slab and the reinforced concrete structure. The main body is a wall member made of precast concrete that constitutes the wall,
A connecting material is buried in the lower end of the concrete of the main body with at least the lower end surface left open and exposed from the lower surface of the wall member main body , and the connecting material has an upper end of a load receiving member that bears the weight of the main body. The lower end of the load receiving member is placed on the top surface of the slab and supported on the top surface of the slab.

In claim 1, "a wall member disposed at a distance from the top surface of the slab" refers to concrete (precast This means that the wall member 2 is arranged (installed) on the slab 8 so that the lower end surface of the slab (concrete) is located at a distance from the top end surface of the slab 8. Cast-in-place concrete 7 is placed between the lower end surface of the wall member main body 2A and the top end surface of the slab 8, and the reinforced concrete wall 1 is completed. The wall member main body 2A includes concrete and vertical reinforcements 5 and horizontal reinforcements 6 arranged inside the concrete, but hereinafter, it may simply refer to concrete.

The fact that the wall member 2 is installed on the slab 8 with the lower end surface of the wall member main body (concrete) 2A spaced apart from the top end surface of the slab 8 means that the connecting material 3 buried inside the wall member main body 2A This is possible because the upper end of the load receiving member 4 is connected from below, etc., and the lower end (lower end surface) of the load receiving member 4 is placed on the top end surface of the slab 8. The load receiving member 4 bears the weight of the wall member main body 2A as an axial compressive force.

The connecting member 3 is buried in the lower end inside the wall member main body 2A, and the load receiving member 4 is connected to this connecting member 3. Therefore, at least the lower end surface of the connecting member 3 remains open, and the lower end of the wall member main body 2A is be exposed from. It is sufficient that at least the lower end surface of the connecting member 3 is exposed from the lower surface of the wall member main body 2A, and the upper part of the connecting member 3 is connected to the wall member with the lower part of the connecting member 3 protruding downward from the wall member main body 2A. It may also be buried within the main body 2A. In the case where the lower part in the axial direction protrudes, a part of the protruding part of the connecting member 3 may be open (cut out) so that the load receiving member 4 can be horizontally moved and connected to the connecting member 3. be.

Specifically, steel materials such as reinforcing bars, hollow steel pipes, non-hollow sections, etc. are used for the load receiving member 4, and the form of the connecting member 3 differs depending on the type of steel material. "Steel materials, etc." includes, in addition to steel materials, materials such as plastics that have the rigidity and strength to maintain connection (connection) with the load receiving member 4 when the wall member 2 is buried in concrete. It is. If the load receiving member 4 is a reinforcing bar, for example, a threaded reinforcing bar with a male thread cut at least at its upper end is used as the reinforcing bar, and a sleeve such as an insert or coupler with a female thread is used as the connecting member 3. When the reinforcing bar is a threaded reinforcing bar, it is basically connected to the connecting member 3 by screwing, but this is not necessarily necessary.

In addition to screwing, there is also a connection in which the connection material 3 is filled with a filler such as mortar, concrete, or adhesive while the load receiving member 4 is inserted into the connection material 3. When the load receiving member 4 is made of a steel material other than a reinforcing bar, the connecting member 3 is a hollow steel material having at least an open lower end in the axial direction into which a steel material can be inserted, for example. In either case, the load receiving member 4 is inserted into the connecting member 3 from below the wall member 2 at the installation location of the wall member 2, and is connected to the connecting member 3. "Mainly" is intended to include cases where the load receiving member 4 is horizontally moved as described above.

For example, as in the example shown in FIG. 2 of Patent Document 2, the wall member main body is open only on one side (one side) in the thickness direction of the lower side (slab side) of the wall member, and the other side (other side) is open. When one side of the wall member in the thickness direction has a height spanning the entire height of the wall body in the height direction, the wall member is supported by the slab in the concrete portion. For example, when the wall member is installed on a slab, the concrete portion on one side in the thickness direction of the wall member that is not open bears the weight of the wall member and supports the wall member on the slab. In contrast, in the present invention, since the lower side of the wall member 2 is open over the entire thickness before concrete 7 is poured, the load receiving member 4 plays the role of supporting the wall member 2 on the slab 8. take charge

The load receiving member 4 has its upper end connected to the connecting member 3 and its lower end (lower end surface) placed on the top surface of the slab 8, so that after the wall member 2 is installed on the slab 8, the wall member 2 Concrete 7 is placed between the concrete 7 and the slab 8, and the wall member 2 is supported by the slab 8 until it develops strength. In this relationship, the axial direction of the load receiving member 4 is in principle oriented in the vertical direction, and the lower end surface abuts against the top end surface of the slab 8 in the axial direction, thereby transmitting the weight of the wall member 2 to the slab 8 while bearing its own weight. "In principle" means that inclinations including errors are allowed to the extent that there is no problem in supporting the wall member 2 on the slab 8.

As shown in FIGS. 3 and 4, the load receiving members 4 are provided within one wall member 2 at intervals in the length direction of the wall member 2, such as at least two locations near both longitudinal ends of the wall member 2. Since a plurality of load bearing members 4 are arranged within one wall member 2, the plurality of load receiving members 4 arranged within one wall member 2 share the weight of one wall member 2. If the lower end of the load receiving member 4 is connected (connected) by embedding it in the slab 8, etc., after the concrete 7 is placed between the wall member 2 and the slab 8, the load receiving member 4 will be connected to the concrete. By being embedded in the wall 7, it can also function to bear the tensile force acting on the wall 1. A plurality of load receiving members 4 may be arranged in a staggered manner or the like in the thickness direction of the wall member 2, but in order to avoid mixing of reinforcing bars within the wall member main body 2A, one load receiving member 4 may be arranged in the thickness direction. The book is appropriate.

With the wall member 2 supported by the slab 8, concrete 7 on the lower side (slab 8 side) is poured on site to complete the reinforced concrete wall 1. The wall member 1 is manufactured in a shape that is open in the thickness direction (both sides), that is, the lower surface of the wall member 2 is opened over the entire thickness of the wall member 2. This makes it possible to work on both sides of the wall member 2 in the thickness direction on the slab 8, so that the workability of reinforcing reinforcement 10 arranged across the wall member 2 and the slab 8 is improved. Even when sufficient working space is not secured on either side of the wall member 2 in the thickness direction, it is possible to secure working space on the other side. The insert reinforcing bars 10 serve to ensure the integrity of the wall member 2 and the slab 8 by being fixed to both the slab 8 and the concrete 7 below the wall member 2.

In addition, since the lower side of the wall member 2 is open in the thickness direction (both sides) of the wall 1, the insert reinforcement 10 protruding from the top surface of the slab 8 and the vertical reinforcement 5 protruding from the lower surface of the wall member 2 are formed. The ability to fill the surrounding area with cast-in-place concrete 7 is also improved. Since the lower side of the wall member 2 is open, concrete 7 can be placed from either side in the thickness direction of the wall member 2.

As shown in FIG. 4, in the main body 2A of the wall member 2, horizontal reinforcements 6 oriented in the length direction (horizontal direction) of the wall 1 and vertical reinforcements 5 oriented in the height direction are arranged. From the viewpoint of handling workability during transportation of the wall member 2, it is reasonable to arrange the vertical reinforcements 5 in a complete state within the wall member main body 2A; It is necessary to connect (joint) the vertical reinforcement 5 that has been reinforced and the vertical reinforcement that will be reinforced on site. On the other hand, if the vertical reinforcements 5 are made to protrude from the lower end surface of the wall member main body 2A as shown in FIG. , workability on site improves accordingly.

A reinforced concrete wall 1 using the wall member 2 according to claim 1 or claim 2 is provided with insert reinforcements 10 protruding from the top surface of the slab 8 toward the wall member 2 side installed in the slab 8. A step of completing the slab 8, a step of installing the load receiving member 4 connected to the connecting member 3 on the slab 8, and supporting the wall member 2 on the slab 8, and a step of supporting the wall member 2 below the wall member 2 and on the slab 8 It is constructed through a step of pouring concrete 7 between them (Claim 3).

As shown in Figure 1, the reinforcing bars 10 are placed in the slab 8 at the bottom with the upper part protruding upward from the top surface of the slab 8, and the slab 8 is completed by placing the slab reinforcing bars 9 and pouring concrete. to (be formed). The slab 8 is mainly constructed by pouring concrete on-site, but it may also be made in advance from precast concrete with the lower part of the reinforcing bars 10 buried in the concrete. In that case, the slab 8 is completed by being installed on a beam or the like at the site. When the slab 8 is constructed on site, the load receiving member 4 is installed on the slab 8 after the slab 8 has demonstrated its ability to support the wall member 2 (after the concrete strength has developed).

The upper end of the load receiving member is connected to the connecting material buried in the lower end of the concrete that makes up the main body of the wall member, and the lower end of the load receiving member is placed on the top surface of the slab. In order to support the wall member on the top surface of the slab, the lower side of the wall member can be manufactured in a shape that is open in the thickness direction of the wall body. As a result, it becomes possible to work on both sides of the wall member in the thickness direction on the slab, improving the workability of reinforcing reinforcement. Furthermore, since the lower side of the wall is open in the thickness direction of the wall, the filling performance of cast-in-place concrete around the reinforcing bars protruding from the top surface of the slab is also improved.

FIG. 3 is a longitudinal cross-sectional view of the wall member when viewed in the length direction, showing how the wall member is installed on the slab and supported by the slab. FIG. 2 is a longitudinal cross-sectional view showing the wall member shown in FIG. 1 when it is held from both sides in the thickness direction by supports for preventing fall. FIG. 3 is a perspective view showing an example of the arrangement of a load receiving member connected to the wall member shown in FIG. 2 and a support for preventing the wall member from falling; FIG. 4 is an elevation view of the wall member showing the relationship between the wall member shown in FIG. 3 in which the vertical reinforcement and the load receiving member protrude from the lower surface of the main body and the insert reinforcement protruding from the top surface of the slab. (a) is a vertical cross-sectional view showing how cast-in-place concrete is placed below a wall member, and (b) shows how concrete is placed in a conventional example in which the entire wall is constructed with cast-in-place concrete. FIG.

Fig. 1 shows a reinforced concrete wall 1 in which cast-in-place concrete 7 is placed between the top end surface of a slab 8, and a wall member 2 whose main body 2A is made of precast concrete is placed on top of the slab 8. It shows how it is placed at a distance from the top surface.

A hollow connecting member 3 to which a load receiving member 4 for supporting the wall member 2 on the slab 8 is connected is buried in the lower end of the concrete (precast concrete) that is the main body 2A of the wall member 2. The upper end of a load receiving member 4 having the ability to bear an axial compressive force is connected to this connecting member 3, while the lower end surface of the load receiving member 4 is placed on the top end surface of the slab 8 and abuts it. As a result, the wall member 2 is supported on the top surface of the slab 8.

In Fig. 1, the purpose is to prevent air bubbles from remaining in the upper part of the concrete 7 between the lower end surface of the main body 2A of the wall member 2 and the concrete 7 placed below it, and to ensure integrity through adhesion. The lower end surface of the main body 2A is sloped in the thickness direction, and unevenness with steps is formed in the thickness direction. Furthermore, while arranging the connecting material 3 on the convex side, a notch 2a is formed on the lower surface side of the convex side and a part of the connecting material 3 in the axial direction is exposed, so that the load receiving member 4 before concrete 7 is poured. This facilitates the connection work to the connecting material 3.

The connecting member 3 has a hollow shape with an open lower end in the axial direction, and is buried in the main body 2A of the wall member 2 with at least the lower end exposed to the outside of the main body 2A. Since the connecting member 3 only needs to surround the load receiving member 4 when connected to the load receiving member 4, the connecting member 3 does not need to have a perfect cylindrical shape, and may have a hollow shape with open sides. The connecting member 3 is made of, for example, steel, fiber-reinforced plastic, etc., but the material is not limited.

The load receiving member 4 is inserted into the connecting member 3 in the axial direction of the load receiving member 4 (connecting member 3), and is inserted into the connecting member 3 by screwing by rotation around the axis. 3 is filled with a filler such as mortar or adhesive, and the connection is made by hardening the filler or the like. When the side surface of the connecting member 3 is open, the load receiving member 4 may be inserted into the connecting member 3 by moving in a direction (horizontal direction) perpendicular to its axial direction. In that case, a portion of the main body 2A (concrete) that is continuous with the open side surface of the connecting member 3 is also cut out.

The load receiving member 4 is made of, for example, a bar with a solid cross section such as a threaded reinforcing bar or a deformed reinforcing bar (deformed steel bar), a bar with a hollow cross section such as a steel pipe, or a non-circular shaped steel. The load receiving member 4 is also made of steel, fiber-reinforced plastic, etc., and the load receiving member 4 has the function of supporting the wall member 2 on the slab 8 by bearing the weight of the wall member 2 as an axial compressive force. The shape and material do not matter. Since the concrete 7 supports the wall member 2 after the concrete 7 poured under the main body 2A develops its strength, the load receiving member 4 only needs to support the wall member 2 until the concrete 7 develops its strength.

As shown in FIGS. 3 and 4, the load receiving members 4 are located at two locations near both ends of the wall member 2 in the length direction (in the axial direction of the horizontal reinforcement 6), or at two locations near the ends of the wall member 2, as shown in FIGS. 3 and 4. Multiple pieces are placed at intervals along the length. Since the plurality of load receiving members 4 connected to this one wall member 2 only need to share the weight of the wall member 2, the burden on one load receiving member 4 is equal to the number of the dead weight of the wall member 2. One is enough.

One or more load receiving members 4 are arranged in the thickness direction of the wall member 2 depending on its shape and compressive force bearing capacity. In the case of one load receiving member 4, in order to support the wall member 2 on the slab 8 so that the wall member 2 is stable against falling, the centroid on the cross section of the wall member 2 must be placed at a position where the center of the load receiving member 4 passes through. It is reasonable to place them. When the wall member 2 is held from both sides in the thickness direction as shown in FIG. There is no need to go through the center of gravity.

Vertical reinforcements 5 and horizontal reinforcements 6 are arranged inside the main body 2A of the wall member 2, but there are two cases in which the vertical reinforcements 5 are arranged completely inside the main body 2A, and when the vertical reinforcements 5 are arranged completely inside the main body 2A, and when the vertical reinforcements 5 are arranged completely in the main body 2A, and when the vertical reinforcements 5 are arranged completely inside the main body 2A, and when the vertical reinforcements 5 are arranged completely inside the main body 2A, and when the vertical reinforcements 5 are arranged completely inside the main body 2A, In order to ensure integrity with the concrete 7 placed in between, reinforcement may be arranged in a state protruding from the lower end surface of the main body 2A. The drawing shows an example in which the lower part of the vertical strip 5 protrudes from the lower end surface of the main body 2A to near the top end surface of the slab 8. The drawing also shows an example where vertical reinforcements 5 and horizontal reinforcements 6 are double arranged inside the main body 2A of the wall member 2 and within the concrete 7, but in addition to single reinforcement arrangement, staggered reinforcement arrangement is also possible. There is also.

Inside the slab 8, in addition to the slab reinforcements 9, insert reinforcements 10 are arranged and fixed in the concrete 7 constituting the wall body 1 to ensure the integrity of the slab 8 and the concrete 7. The slab 8 may be constructed by arranging reinforcing bars 10 or the like and placing cast-in-place concrete, or it may be manufactured from precast concrete.

The reinforcing reinforcement 10 has two parts: a fixed part 10a buried in the slab 8, and a rising part 10b that protrudes from the top surface of the slab 8 toward the wall member 2 and is reinforced in the concrete 7 below the wall member 2. In the drawing, reinforcing bars 10 are arranged parallel to each other in the thickness direction in the concrete 7 due to the double reinforcing bars arranged inside the main body 2A.

In order to ensure the clearance between the vertical reinforcements 5 in the concrete 7 placement area, the rising portions 10b of the insert reinforcements 10 are located between the adjacent vertical reinforcements 5 and 5 in the length direction of the wall member 2, as shown in FIG. It is appropriate to arrange the reinforcement so that it is arranged in the following manner. This is not necessarily necessary if the spacing between the insertion strips 10 and the vertical strips 5 is ensured in the thickness direction of the wall member 2. In FIGS. 1 and 2, vertical reinforcements 5 and insertion reinforcements 10 are arranged on the same line in the length direction of the wall member 2, and when viewed in the length direction of the wall member 2, the insertion reinforcements 10 overlap the vertical reinforcements 5. However, it may shift in the thickness direction of the wall member 2.

When the slab 8 is constructed using cast-in-place concrete, it is constructed by arranging slab reinforcements 9 and insert reinforcements 10 on a floor form and pouring concrete. After the strength of the concrete has been developed, the wall member 2 with the load receiving member 4 connected to the connecting member 3 is installed on the top end of the slab 8. The wall member 2 is installed on the slab 8 by abutting the lower end of the load receiving member 4 against the top surface of the slab 8 or by connecting it to a connecting material buried within the slab 8. When installing the wall member 2, in order to ensure the accuracy of the installation of the wall member 2, supports 11 to prevent falling are installed between both sides of the wall member 2 in the thickness direction and the slab 8, as shown in FIGS. 2 and 3. be done.

When the wall members 2 are arranged adjacent to each other in the length direction, a connecting member 12 is provided between the adjacent wall members 2, 2 as shown in FIG. 3, and the adjacent wall members 2, 2 are connected to each other. However, the continuity of the wall members 2, 2 is ensured. The connecting member 12 is joined to each wall member 2 by bolts 13 or the like. In FIG. 1, an insert 14 is embedded in the wall member 2 at the insertion position of the bolt 13, and the bolt 13 is screwed into this insert 14, but the method of joining the connecting member 12 to the wall member 2 is arbitrary. be.

After the wall member 2 is installed, as shown in FIG. will be established. (b) shows the state of concrete pouring when the entire wall is conventionally constructed using cast-in-place concrete. In the example shown in (b), it is necessary to erect scaffolding on the slab to a position higher than the top of the wall, but in the present invention, the concrete 7 only needs to be placed below the wall member 2. Since there is no need to erect scaffolding on the slab 8, work efficiency on site is improved. FIG. 5-(a) shows concrete 7 being poured from the right side of the wall member 2, and vibrations being applied to the concrete 7 from the left side.

1...Wall body,
2... Wall member, 2A... Main body, 2a... Notch,
3...Connecting material,
4...Load receiving member,
5...Vertical stripe, 6...Horizontal stripe,
7...(cast-in-place) concrete,
8...Slab, 9...Slab line,
10... insertion line, 10a... fixing part, 10b... rising part,
11...Support,
12... Connecting material, 13... Bolt, 14... Insert,
15... Sewer board.

Claims (3)

A wall member whose main body is made of precast concrete, which is placed on a slab at a distance from the top surface of the slab, and where concrete is cast between the top surface and the top surface of the slab to constitute a reinforced concrete wall. and
A connecting material is buried in the lower end of the concrete of the main body with at least the lower end surface left open and exposed from the lower surface of the wall member main body , and the connecting material has an upper end of a load receiving member that bears the weight of the main body. A wall member for forming a wall body, wherein the lower end of the load receiving member is placed on and supported on the top surface of the slab. 2. The wall member for forming a wall body according to claim 1, wherein vertical reinforcements arranged inside the main body protrude from a lower end surface of the main body. A method of constructing a reinforced concrete wall using the wall member according to claim 1 or 2,
a step of constructing the slab with a reinforcing bar protruding from the top surface of the slab toward the wall member installed in the slab; and installing the load receiving member on the slab with the load receiving member connected to the connecting material. and the wall body is constructed through a step of supporting the wall member on the slab, and a step of pouring concrete between the bottom of the wall member and the top of the slab. How to build.

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